Process of treating fabrics with ethylene carbonate and article produced therefrom



Jan. 26, 1965 J. J. HIRSHFELD 3,167,448

PROCESS OF TREATING FABRICS WITH ETI-IYLENE CARBONATE AND ARTICLEPRODUCED THEREFROM Filed Aug. 23, 1961 NA PPED FABRIC COMPOSED OF.FIBERS OF AT LEAST 809/0 ACRYLONITRILE.

IMPREGNATE NAP WITH AQUEOUS ETHYLENE CARBONATE AND SILICONE RESINEMULSION.

DRY TO EVAPORATE WATER AND CURE THE SILICONE RESIN.

FIG. I.

ETHYLENE CARBONATE BOND k mmymmwm NAP rV/ /?\-FABRIC F l INVENTOR.

JULIAN J. HIRSI-IFELD 3,167,448 Patented Jan. 26., 1965 Deiaware FiledAug. 23, 1961, Ser. No. 133,299 16 Claims. (Cl. 117138.8)

This invention is concerned with the treatment of the raised surface ofwoven, non-woven and knitted synthetic fabrics to prevent distortion ofthe raised surface due to normal wearing and laundering conditions. Morespecifically, this invention is concerned with preventing the matting,shedding and pilling of the nap of acrylic fabrics after subjectingthese fabrics to normal laundering and wearing conditions, as well aspreserving a soft hand.

In the past the raised surfaces of fabrics composed of synthetic fibershave been stabilized by the use of salts which were toxic and corrosive;therefore, special and expensive production equipment was necessary toapply these salts, usually as a solution, to the raised surface of thefabrics. Some of the salts were the pure metal halides such as zincchloride, lithium bromide and water soluble thiocyanates. These saltswere very corrosive to the standard finishing mill equipment. Inaddition. these salts gave the fabrics a harsh hand which was veryundesirable and affected the color to such an extent that the fabricswere unacceptable. While this harsh or crisp hand could be softened,this entailed additional chemical and physical treatments which added toits cost.

An object of this invention is to provide a method by which the nap ofsynthetic fabrics are stabilized against normal wearing and launderingconditions.

Another object of this invention is to provide a stabilizing agent toprevent excessive matting, pilling and shedding of the nap of syntheticfabrics.

Another object of this invention is to provide a stabilizing agent forthe nap of synthetic fabrics which gives a soft hand.

Another object of this invention is to provide a stabilizing agent forthe nap of synthetic fabrics which does not deleteriously affect thecolor.

Another object of this invention is to provide a stabilizing agent forthe nap of acrylonitrile fabrics which renders the fabrics free ofexcessive matting, pilling and shedding under normal launderingconditions as well as normal wearing conditions.

Another object of this invention is to provide permanent stability ofhigh pile fabrics against matting, pilling and shedding.

Other objects and advantages of this invention will become apparent fromthe hereinafter detailed description.

The objects of this invention are generally accomplished by applying anaqueous solution of ethylene carbonate to the nap or raised surface ofsynthetic fabrics, either woven, non-woven or knitted. Thiscompound isapplied by the conventional padding method. In addition to the ethylenecarbonate, a silicone emulsion is also padded into the fabrics. The useof the silicone' emulsion results in an acceptable soft hand when usedin conjunction with the ethylene carbonate. In addition an anti-staticagent such as Aston 108, which is a polyamine resin such asdiethylenetriamine crossed-linked with polyethylene glycol diiodide oran epoxy resin, may be used inv conjunction with the silicone emulsionand ethylene carbonate which will give excellent protection againststatic electricity. Also, the fabric maybe treated with the above agentsand a water repellent-agent such as Phobotex F.T.C., a melaminederivative, which will not afiect the hand or color and will giveexcellent resistance to water penetration. The use of these additionalagents give additional useful properties to the fabrics withoutaffecting the hand and color.

More specifically, the synthetic fabrics were mapped and then treatedwith an aqueous solution of ethylene carbonate in the range of a 0.05percent solution to a 50 percent solution with the preferred solutionbeing a 0.5 percent to a 2.0 percent solution. Along with the ethylenecarbonate solution an aqueous non-ionic silicone emulsion of the generalformula S1O Li. J.

with R and R being generally aliphatic radicals and n being from 1 tooowere added to improve the hand of the treated and napped syntheticfabric. An aqueous emulsion of the silicone of from 0.2 percent to 5percent may be used with the preferred being a 1 percent to a 2 percentemulsion. More than a 5 percent emulsion may be used, but there is noimprovement in the hand above the 5 percent emulsion and only increasesthe cost. The napped and treated fabrics were then heated in aconventional fabric drying apparatus, such as a chain dryer, toevaporate the water and to cure the softening agent-the silicone; inaddition, this stabilizing compound, ethylene carbonate, is concentratedat the points of intersection of the fibers in the nap to form a durablebond between and among themselves. The period of time the fabrics wereheated ranged from 5 minutes to 60 minutes, with the preferred being 20minutes, at a temperature of 240 F. to 300 F., with the preferredtemperature being 280 F. If an aqueous ethylene carbonate solution isused alone. then the exact temperature is immaterial as long as thefabrics so treated are dried; however, the temperature must not go tothe degradation point of the acrylic fibers, 350 F. The napped fabricswere then withdrawn from the drying apparatus, and it was found that thehand was of acceptable softness and the color was unaffected. Thestabilizing compound and softening agent were added onto the nap by theconventional padding method which is known in the textile field. Otheragents such as water repellents and anti-static agents may have beenadded to the original padding bathwhich would have resulted in givingthe mapped fabric, not only stability to laundering and wearing, but asofthand and permanent anti-static and water repellent properties.

While this application has been generally directed to synthetic fabrics,it is'especially useful in the stabilizing of the nap of fabrics madefrom fibers of acrylic polymers. The polymeric materials, which may beemployed in the practice of the present invention, arepolyacrylonitrile, copolymers, including binary and ternary polymerscontaining at least percent by weight of acrylonitrile in the polymermolecule, ora blend comprising polyacrylonitrile or copolymerscomprising acrylonitrile with from 2 to 50 percentof another polymericmaterial, the blend having an overall polymerized acrylonitrile contentof at least 80 percent by weight. While the preferred polymers employedin the instant invention are those containing at least 80 percent ofacrylonitrile, generally recognized as the fiber-forming acrylonitrilepolymers, it will be understood that the invention is likewiseapplicable to polymers containing less than 80 percent acrylonitrile.The acrylonitrile polymers containing less than 80 percent acrylonitrileare useful in forming films, coating compositions, molding operations,lacquers, etc., in all of which applications the alleviation ofundesirable color is extremely important.

For example, the polymer may be a copolymer of from 80 to 98 percentacrylonitrile and from 2 to 20 percent 7 tion.

of another monomer containing the C linkage and copolymerizable withacrylonitrile. Suitable mono-olefinic monomers include acrylic,alpha-chloroacrylic and methacrylic acids; the acrylates, such asmethylmethacrylate, ethylmethacrylate, butylmethacrylate, methoxymethylmethacrylate, beta-chloroethyl methacrylate, and the correspondingesters of acrylic and alpha-chloroacrylic acids; vinyl chloride, vinylfiuoride, vinyl bromide, vinylidene chloride, l-chloro-l-brmo-ethylene;methacrylonitrile; acrylamide and methacrylarnide;alpha-chloroacrylamide; or monoalkyl substitution products thereof;methylvinyl ketone; vinyl carboxylates, such as vinyl acetate, vinylchloroacetate, vinyl propionate, and vinyl stearate; N-vinylimides, suchas N-vinylphthalimide and N-vinylsuccinimide; methylene malonic esters;itaconic acid and itaconic esters; N-vinylcarbazole; vinyl furane; alkylvinyl esters; vinyl sulfonic acid; ethylene alpha, betadicarboxylicacids or their anhydrides or derivatives, such as diethylcitraconate,diethylmesaconate, styrene, vinyl naphthalene; VinyLsubstituted tertiaryheterocyclic amines, such as the vinylpyridines and alkyl-substitutedvinylpyridines, for example, 2-vinylpyridine, 4-vinylpyridine,Z-methyl-5-vinylpyridine, etc.; l-vinylimidazole and alkylsubstitutedl-vinylimidazoles, such as 2-, 4-, or S-methyll-vinylimida'zole, andother C=C containing polymerizable materials.

The polymer may be a ternary or higher interpolymer, for example,products obtained by the interpolymerization of acrylonitrile and two ormore of any of the monomers, other than acrylonitrile, enumerated above.More specifically, and preferably, the ternary polymer comprisesacrylonitrile, methacrylonitrile, and 2-vinylpyridine. The ternarypolymers preferably contain from 80 to 98 percent of acrylonitrile, from1 to percent of a vinylpyridine or a l-vinylimidazole, and from 1 to 18percent of another substance such as methacrylonitrile or vinyl Vchloride.

The polymer may also be a blend of a polyacrylonitrile or of a binaryinterpolymer of from 80 to 99 percent acrylonitrile and from 1 to 20percent of at least one other C=C containing substance with from 2 to 50percent of the weight of the blend of a copolymer of from 10 to 70percent of acrylonitrile and from to 90 percent of at least one otherC=C containing polymerizable monomer. Preferably, when the polymericmaterial comprises a blend, it will be a blend of a copolymer of 90 to98 percent acrylonitrile and from 2 to 10 percent of anothermonomer-olefinic monomer, such as vinyl acetate, which is not receptiveto dyestuff, with a sufficient amount of a copolymer of from 10 to 70percent of acrylonitrile and from 30 to 90 percent of a vinylsubstitutedtertiary heterocyclic amine, such as vinylpyridine or l-vinylimidazole,to give a dyeable blend having an overall vinyl-substituted tertiaryheterocyclic amine content of from 2 to 10 percent, based on the weightof the blend.

The following examples are cited to illustrate the inven- They are notintended to limit it in any way. Unless otherwise noted, percentages asexpressed in the examples indicate percent by weight. 7 r

. Example 1 A swatch of nappedfabric composed of synthetic, linearacrylonitrile polymers was padded with an aqueous solu- Example 2Example 3 A swatch of napped acrylic fabric composed of fibers of ablend of 88 percent or one copolymer of 94percent acrylonitrile and 6percent vinyl acetate and 12' percent of another copolym er composed of5 0 percent acrylonitrile and percent methyl vinyl pyridine was paddedwith a 0.50 percent aqueous solution of ethylene carbonate. The

swatch was then placed in a drying oven and heated for' 20 minutes at220 F. It was then removed and allowed to cool, after which the swatchwas laundered five consecutive times under normal laundering conditions.There was no appreciable change in the soft hand which would affect itscommercial acceptability-and the color was not affected. In additionthere was no excessive amount of matting, pilling or shedding.

Example 4 A swatch of napped fabric composed of fibers of 92 percentacrylonitrile and 8 percent vinyl acetate was padded with a 0.25 percentaqueous solution of ethylene carbonate. 1 The swatch was then placed ina drying oven and heated for 20 minutes at 220 F. It was then removedand allowed to cool, after which the swatch was laundered fiveconsecutive times under normal laundering conditions. The hand remainedvery soft and the color was not affected. In addition there was noexcessive amount of matting, pilling or shedding.

Example 5 A swatch of napped fabric composed of fibers of 92 percentacrylonitrile and 8 percent vinyl acetate was padded with a 0.10 percentaqueous solution of. ethylene carbonate. The swatch was then placed in adrying oven and heated for 20 minutes at 220 F. It was then removed andallowed to dry, after which the swatch was laundered. five consecutivetimes under normal laundering conditions. The hand remained very softand the color was not affected. :In addition there was no exces .siveamount of matting,pilling' or shedding.

Example 6 percent of sodium bisulfate, a catalyst. The swatch was thenplaced in a drying oven and heated for 20 minutes at 220 F. Thetemperature was then raised to 280 F. for ten minutes to cure thesilicone. It was then removed and allowed to cool, after which theswatch was laun dered for five consecutive times under normal launderingIt was then removed and allowed to cool, after conditions. The handremained very soft and the color was not affected. In addition there wasno excessive amount of matting, pillingor shedding.

Example 7 A swatch of napped fabric composed of fibers of 92 percentacrylonitrile and 8 percent vinyl acetate was padded with an aqueoussolution composed of 0.5 percent ethylene carbonate, 2.0 percentsilicone resin and 0.2 7

percent sodium bisulfate, a catalyst. The swatch' was then placed in adrying, oven where it was heated for 20 minutes at 220 F. Thetemperature of the oven was then raised to 280 F. for minutes to curethe silicone resin. It was then removed from the oven and allowed tocool, after which the swatch was laundered five consecutive times undernormal laundering conditions. The hand remained very soft and the colorwas not affected. In addition there was no excessive amount of matting,pilling or shedding.

With the stabilizing compound of this invention, it is possible to treatnapped fabrics composed of acrylic fibers so that they may be launderedmany times and their hand, color and physical properties, such asmatting, pilling and shedding will not be appreciably changed from theiroriginal conditions.

Many modifications of the above will be obvious to those skilled in theart without a departure from the inventive concept.

I claim:

1. An article composed of the napped fabric of fibers of syntheticlinear acrylonitrile, ethylene carbonate as a bonding agent at the pointof intersection of the fibers in the nap and a silicone resin as asoftening agent.

2. The article of claim 1 in which the fabric is composed of fibers ofat least 80 percent acrylonitrile and up to 20 percent of anothercopolymerizable mono-olefinic monomer.

3. The article of claim 2 in which the fabric is composed of fibers of94 percent acrylonitrile and 6 percent vinyl acetate.

4. The article of claim 2 in which the fabric is composed of fibers of ablend of 88 percent of one copolymer of 94 percent acrylonitrile and 6percent vinyl acetate and 12 percent of another copolymer of 50 percentacrylonitrile and 50 percent methyl vinyl pyridine.

5. An article composed of the napped fabric of fibers of syntheticlinear acrylonitrile and ethylene carbonate used as a bonding agent atthe point of intersection of the fibers in the nap.

6. A method of stabilizing the nap of fabrics composed of fibers ofsynthetic linear polymers of acrylonitrile, comprising impregnating thenapped fabric with an aqueous solution of ethylene carbonate and asilicone resin in which the ethylene carbonate as a bonding agent isused in an amount of from 0.05 percent to 50 percent by weight of thesolution, drying said fabric and curing the silicone resin by heatingsaid fabric at a temperature of from 240 F. to 300 F. for 5 to 60minutes.

7. The method of claim 6 in which the napped fabric is treated with anaqueous solution of ethylene carbonate.

8. The method of claim 6 in which the fabric is composed of fibers of atleast 80 percent acrylonitrile and up to 20 percent of anothercopolymerizable mono-olefinic monomer.

9. The method of claim 8 in which the fiber is composed of 94 percentacrylonitrile and 6 percent vinyl acetate.

10. The method of claim 8 in which the fiber is composed of a blend of88 percent of one copolymer of 94 percent acrylonitrile and 6 percentvinyl acetate and 12 percent of another copolymer composed of 50 percentacrylonitrile and 50 percent methyl vinyl pyridine.

11. The method of claim 7 in which the fabric is composed of fibers ofat least percent acrylonitrile and up to 20 percent of anothercopolymerizable monomer.

12. The method of claim 11 in which the fibers are selected from thegroup consisting of a fiber of 94 percent acrylonitrile and 6 percentvinyl acetate and a blend of 88 percent of one copolymer of 94 percentacrylonitrile and 6 percent vinyl acetate and 12 percent of anothercopolymer composed of 50 percent acrylonitrile and 50 percent methylvinyl pyridine.

13. A method of stabilizing the nap of fabrics composed of fibers of atleast 80 percent acrylonitrile and up to 20 percent of anothercopolymerizable mono-olefinic monomer, comprising impregnating thenapped fabric with an aqueous solution of ethylene carbonate in whichethylene carbonate acts as a bonding agent at the point of intersectionof the fibers in the nap to form a durable bond, with the amount ofethylene carbonate being 0.5 percent to 2.0 percent by weight of thesolution, and drying said fabric.

14. A method of stabilizing the nap of fabrics composed of fibers of atleast 80 percent acrylonitrile and up to 20 percent of anothercopolymerizable mono-olefinic monomer, comprising impregnating thenapped fabric with an aqueous solution of ethylene carbonate, in therange of a 0.05 percent to a 50 percent solution, with ethylenecarbonate acting as a bonding agent at the point of intersection of thefibers in the nap to form a durable bond, and a silicone resin emulsionin the range of 0.2 percent to 5 percent solution, drying said fabricand ouring the silicone resin by heating said fabric to 280 F. for 10minutes.

15. The method of claim 13 in which the aqueous solution of ethylenecarbonate is a 1 percent solution.

16. The method of claim 14 in which the aqueous solution of ethylenecarbonate is a 1 percent solution and the silicon resin is 1 to 2percent emulsion.

Dennett Mar. 11, 1952 Jones et al Feb. 7, 1956

6. A METHOD OF STABILIZING THE NAP OF FABRICS COMPOSED OF FIBERS OFSYNTHETIC LINEAR POLYMERS OF ACRYLONITRILE, COMPRISING IMPREGNATING THENAPPED FABRIC WITH AN AQUEOUS SOLUTION OF ETHYLENE CARBONATE AND ASILICONE RESIN IN WHICH THE ETHYLENE CARBONATE AS A BONDING AGENT ISUSED IN AN AMOUNT OF FROM 0.05 PERCENT TO 50 PERCENT BY WEIGHT OF THESOLUTION, DRYING SAID FABRIC AND CURING THE SILICONE RESIN BY HEATINGSAID FABRIC AT A TEMPERATURE OF FROM 240*F. TO 300*F. FOR 5 TO 60MINUTES.